Maybe it’s because the media likes to drag out these kinds of narratives for the sake of keeping up the drama. Maybe it’s because it’s been two months since the most recent arrests. Or maybe it’s because Donald Trump’s desperate last minute antics are being seen as something other than desperate last minute antics. But for one reason or another, there’s a general perception that the Robert Mueller probe is inching along and is nowhere near getting to Trump. But the evidence says the precise opposite. You just have to know how to interpret it.

In any investigation of this kind, prosecutors start with the little fish and work their way up. They aim for as many plea deals and cooperating witnesses as they can along the way, so they can build an airtight case against the kingpin. By the time they’re ready to interview the kingpin, it’s over. Either they have enough evidence in handx to nail the kingpin no matter what he says, or they have no evidence and the kingpin interview is just a formality.

We saw the latter when the FBI interviewed Hillary Clinton about her emails in 2016. By that time they had read and researched every one of her emails, interrogated every one of her underlings, and they knew with 100% certainty that she hadn’t done a damn thing wrong. It’s why she was eager to get her interview over with; she knew that as soon as it finished, they’d announce that they’d clear her of any wrongdoing. The Trump-Russia investigation is on the same path, but it’s about to have the opposite result.

By now we know that Mueller has a slew of key cooperating witnesses and a metric ton of hard evidence that Donald Trump committed felony obstruction of justice. Mueller now wants to interview Trump because that’s the last step before dropping the hammer on him. Mueller already knows what happened; all that’s left is for Trump to confess to it, or get caught lying about it. Mueller has made clear that he wants the Trump interview to happen ASAP. Trump’s legal team says he’ll refuse, but that’s fine, because Mueller has him nailed by now anyway. So the obstruction portion of the Trump-Russia investigation is already basically complete.

There are several other aspects of the Trump-Russia investigation. Mueller is also apparently pursuing Donald Trump for everything from money laundering to conspiracy against the United States. We don’t know how far along those aspects of the probe are, because Mueller has kept that tightly under wraps. But the obstruction of justice component, the quickest and easiest charge to prove, and the charge that took Richard Nixon down, is essentially at the finish line. Trump will make his choice about the interview, and then Mueller will nail him.